with the daring operation if the waters off of italy, the likes of which has never been attempted. Engineers right now are trying to pull the ocean liner "costa concordia" upright. It capsized some 20 months ago, killing 3peop2 people. Just moments ago, crews reported their first big success. Abc's lama hasan is there. Lama? Reporter: And good morning to you, josh. Overnight, a violent thunderstorm was battering the island, delaying the operation for three hours. Engineers are saying they've managed to dislodge the "costa concordia" from the reef. This morning, the biggest salvage procedure in maritime history to rotate the 950-foot "costa concordia" is fully under way. In the unprecedented operation, engineers are beginning to dislodge the hull from the reef. 48 hydraulic jacks and cables underneath the ship will move it. You can see the massive white flotation devices on the side ready to use once it is vertic vertical. Engineers are watching live cameras attached to unmanned sub marines, constantly monitoring the stress of the cruise liner. Everything will be taking a lot of strain during the operation. You cannot do it again. One time, a one-chance opportunity. Reporter: A highly complicated operation. There is no predicting what will happen. The ship could break apart, causing an environmental disaster or roll back on its side. It could take 1 hours to get the ship upright. Engineers say it is critical. It is now or never, because the "costa concordia" will not be

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Costa Concordia Captain: Others Must 'Share the Blame'

Francesco Schettino gives his side of the story in deadly cruise ship crash.

Cruise Ship Adrift in Pirate Waters

The sister ship of the Costa Concordia is stranded in the Indian Ocean.

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